This document summarizes and compares three pulse width modulation techniques - sinusoidal PWM (SPWM), third harmonic injection PWM (THIPWM), and space vector PWM (SVPWM) - for a three-phase voltage source inverter. SPWM is the simplest technique but has drawbacks like higher total harmonic distortion and lower switching frequency. THIPWM provides better THD than SPWM. SVPWM shows lower THD than both SPWM and THIPWM, especially in overmodulation regions and at high frequencies. The document presents the theoretical principles, simulation models, and results of the three techniques, showing that SVPWM achieves the best performance and meets current harmonic standards.